1. Field of the Invention
Systems consistent with the present invention relate to an autostereoscopic display system, and more particularly, to an autostereoscopic display system having a simple optical structure in which an image for a left eye is guided to a left eye of a viewer and an image for a right eye is guided to a right eye of the viewer.
2. Description of the Related Art
Examples of a three-dimensional image display method using an image panel, such as a cathode ray tube (CRT), a plasma display panel (PDP), or a projection display, include a stereoscopic image display method. To see a stereoscopic image by using the stereoscopic image display method, a parallax barrier should be disposed in proximity of an image panel, or a viewer should wear shutter glasses.
FIG. 1 is a schematic view of a conventional parallax barrier-type stereoscopic image device. Referring to FIG. 1, the conventional parallax barrier-type stereoscopic image device includes an image panel 10 and a parallax barrier 20 disposed in front of the image panel 10. An image for a left eye and an image for a right eye are alternately alternatively arranged in vertical pixels of the image panel 10. For example, odd-number vertical pixels display the image for a left eye, and even-number vertical pixels display the image for a right eye. In the parallax barrier 20, light transmission regions 20a and light shield regions 20b, each of which has a vertical stripe shape, are alternately aligned. The alternately aligned light transmission regions 20a and light shield regions 20b correspond to the vertical pixels of the image panel 10, respectively. In such a structure, the images for left and right eyes of the image panel 10 have a predetermined orientation when viewed through the parallax barrier 20, and thus the image for a left eye is guided to the viewer's left eye and the image for a right eye is guided to the viewer's right eye. That is, half of the entire pixels of the image panel 10 are used to display the image for a left eye and the other half is used to display the image for a right eye. Therefore, the resolution of the stereoscopic image is half the resolution of a 2-dimensional image of the image panel 10. In order to use the resolution of a 2-dimensional image of the image panel 10 itself as the resolution of the stereoscopic image, the conventional parallax barrier-type stereoscopic image device needs an active-type light shutter, which alternately changes the light transmission regions 20a and light shield regions 20b of the parallax barrier 20, as the parallax barrier 20.
FIG. 2 is a schematic view of a conventional glasses-type stereoscopic image display system. Referring to FIG. 2, the conventional glasses-type stereoscopic image display system includes an image panel 50 which alternately displays an image for a left eye and an image for a right eye, and shutter glasses 60 which are synchronized with the alternative image display and selectively shields a left eye or a right eye. The shutter glasses 60 include a liquid crystal 61 and transparent electrodes 62, 63, and 64, wherein the transparent electrode 62 is disposed on one surface of the liquid crystal 61 and the transparent electrodes 63 and 64 are disposed on the other surface of the liquid crystal 61. The shutter glasses 60 shield or transmit light based on the principle that a polarization of the light which is transmitted through the liquid crystal varies when a voltage is applied or not. In this regard, the shutter glasses 60 are synchronized with a vertical synchronizing signal of the image panel 50, and a viewer alternately watches the image for a left eye and the image for a right eye which are alternately displayed on the image panel 50.
However, in the conventional parallax barrier-type stereoscopic image device, the size of the parallax barrier 20 should be almost similar to that of the image panel 10. Therefore, to obtain a large-screen stereoscopic image, the size of the parallax barrier 20 should be increased and thus the manufacturing costs are increased. Also, the alternately aligned light transmission and shield regions of the parallax barrier 20 should precisely correspond to pixels of the image panel 10, respectively. In addition, the image panel 10 should be a flat panel and location of pixels should be precisely defined therein.
In the conventional glasses-type stereoscopic image display system, a user, that is, a viewer should wear glasses, such as shutter glasses.